1. Field of the Invention
The present invention relates to a useful thermosetting foamable organopolysiloxane composition and a process of curing the same for use in construction materials, automobile materials and others.
2. Description of the Prior Art
Since organopolysiloxane polymers have excellent weather resistance and heat resistance, organopolysiloxane(silicone) foams have come to be widely used in construction materials, automobile materials, etc. in recent years. In the circumstances, how to mix a separately devided foamable material effectively is an important issue, because the foamable material used as raw materials for the construction and automobile materials are normally made up of two or more separate liquid parts (called sides or packs).
According to the conventionally used foamable materials and their curing process, a room temperature-curable foamable material consisting of two or more liquid parts is measured, mixed by hand, injected into a given place, followed by foaming and curing. However, for better conformity with a mass-production line, foamable materials are changing from a room temperature-curable type to a thermosetting type and mixing is changing from manual mixing to mechanical mixing in a blender. The shift of the foamable materials to the thermosetting type contributes to improvement in the speed of a production line and in the product quality because the foamable materials are not influenced by outside air temperature. Furthermore, mechanical mixing is effective in preventing errors in measuring and insufficient mixing.
However, if a conventional room temperature-curable foamable material is used intact as a thermosetting foamable material, a problem arises that foaming and curing start at normal temperature (room temperature) when the liquid parts are mixed and, therefore, it is impossible to secure homogeneous foam cells in the mass production line.